A Kinetic Investigation of the Mechanisms of Radiation-Induced Strand Breakage in DNA Model Systems

  • George D. D. Jones
  • Peter O’Neill
Conference paper
Part of the NATO ASI Series book series (volume 54)


Time-resolved reductions in the light scattering intensity (LSI) of N2O or oxygenated aqueous solutions of single stranded homologous polynucleotides, following pulse irradiation, have been studied as indicies of strand breakage (s.b.) (for a review of the LSI method see Schnabel 1979). With doses of 3–24Gy/pulse, a number of kinetically distinct modes of breakage are apparent. For the polypyrimidines, poly C and poly U, these include i) a small proportion of fast strand breaks (τ½ = 50μs) arising from the direct action of OH-radicals at the sugar phosphate backbone, and ii) major, slower first order routes to breakage that proceed through base radical mediated pathways (Figure 1) (Lemaire et al. 1984).


Polymer Degradation Light Scattering Intensity Kinetic Investigation Strand Breakage Radiat Biol 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

  • George D. D. Jones
    • 1
  • Peter O’Neill
    • 1
  1. 1.Division of Molecular ProcessesMRC Radiobiology UnitChilton, Didcot, OxonUK

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